The invention relates to a casting mass, in particular, for the production of kitchen sinks, molded sanitary articles, kitchen worktops or the like, comprising a syrup based on an acrylate monomer as well as an inorganic filler material which constitutes a proportion of 45 to 85% by weight of the casting mass. The invention relates, in addition, to kitchen sinks, molded sanitary articles and kitchen worktops produced with the use of such casting masses.
Such molded articles are normally subject to considerable abrasive wear and tear as well as temperature stressing and so abrasion resistance as well as the resistance to hot and cold cycles are of fundamental importance. It is known from EP 0 361 101 A1 to use filler materials in casting masses of this type which have an unbroken grain shape. Since it is possible with these filler particles to achieve not only good flow properties for the casting mass itself and, therefore, a simplification of the production of the molded articles but it is, in addition, also possible to achieve relatively high packing densities of the filler particles in the surrounding acrylate matrix, one of the main preconditions for a good abrasion resistance of the molded articles, casting masses of this type have manifold uses.
In practice, it has been shown again and again that so-called flow lines occur on the finished molded part, in particular, in the case of more ambitious shapes of the molded articles to be produced. This applies, for example, for kitchen sinks with twin basins or, however, also for molded articles with larger unstructured surface areas, such as, for example, unstructured draining surfaces of kitchen sinks or also for kitchen worktops. Flow lines are to be understood as a directional preference of the filler particles in flow direction of the casting mass which is caused by the filling process, is visually noticeable and, therefore, unwanted. Such an unwanted directional preference is also obtained when the unbroken grain shapes suggested in EP 0 361 101 are used as filler particles which have a low aspect ratio and should, therefore, actually be more insusceptible with respect to a directional preference during the flow of the casting mass.
Depending on the degree of prominence of these flow lines, kitchen sinks or worktops, in particular, are considered to be no longer sellable in accordance with defined quality characteristics and must, consequently, be separated out and disposed of.
In addition, problems repeatedly occur in the case of the casting masses described at the outset in that cavity formations occur in the vicinity of the surfaces, in particular, in the case of high filler proportions and these likewise result in kitchen sinks or molded articles consisting of such casting masses having to be considered to be no longer sellable.
The object of the present invention is to reduce the scrap rate linked to the aforementioned flaw characteristics during the production of molded articles, in particular, in the case of kitchen sinks, molded sanitary articles and kitchen worktops and, accordingly, to suggest a casting mass suitable for this purpose.